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Unveiling the secrets of diatom-mediated calcification: Implications for the biological pump

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Science china Earth Sciences 2024年第9期67卷 2895-2909页

作者： Yiwen PAN Yifan LI chen-Tung arthur cHEN Zong-Pei JIANG Wei-Jun cAI Yunwen SHEN Zesheng DING Qixian cHEN Yanan DI Wei FAN chenba ZHU Ying cHEN Ocean college Zhejiang University Hainan Institute of Zhejiang University Department of Oceanography Sun Yat-Sen University School of Marine Science and Policy University of Delaware carbon Neutral Innovation Research center Xiamen University

Siliceous diatoms are one of the most prominent actors in the oceans, and they account for approximately 40% of the primary production and particulate organic carbon export flux. It is believed that changes in carbon flux caused by variations in diatom distribution can lead to significant climate shifts. Although the fundamental pathways of diatom-driven carbon sequestration have long been established, there are no reports of cacO3precipitation induced by marine diatom species. This manuscript introduces novel details regarding the enhancement of aragonite precipitation during photosynthesis in Skeletonema costatum in both artificial and natural seawater. Through direct measurements of cell surfaces via a pH microelectrode and zeta potential analyzer, it was determined that the diatom-mediated promotion of cacO3precipitation is achieved through the creation of specific microenvironments with concentrated [cO32–] and [ca2+] and/or the dehydrating effect of adsorbed ca2+.Based on this mechanism, it is highly plausible that diatom-mediated calcification could occur in the oceans, an assertion that was supported by the significant deviation of total alkalinity（TA） from the conservative TA-salinity mixing line during a Skeletonema costatum bloom in the East china Sea and other similar occurrences. The newly discovered calcification pathway establishes a link between particulate inorganic and organic carbon flux and thus helps in the reassessment of marine carbon export fluxes and cO2sequestration efficiency. This discovery may have important ramifications for assessing marine carbon cycling and predicting the potential effects of future ocean acidification.

关键词： Diatom bloom Skeletonema costatum calcification Biological carbon pump counter carbonate pump

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A toast to a zebrafish germ cell induction cocktail

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Science china(Life Sciences) 2024年第6期67卷 1314-1315页

作者： Mary c.Mullins Department of cell and Developmental Biology University of Pennsylvania Perelman School of MedicinePhiladelphia 19104USA

The zebrafish field is ringing in the new year with a publication from Yonghua Sun's laboratory(Wang et al.,2023)of a cocktail of germline factors that can induce all cells of the zebrafish embryo into primordial germ cells(PGcs)at phenomenal *** major advance is not only of great interest to germ cell biologists,but it has important applications to the entire zebrafish field,as shown in Wang et al.(2023).

关键词： fish zebra field

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Broad Hormonal Responses Induced by Aluminum in Roots of Dwarf Transgenics of Solanum lycopersicum L. cv “Micro-Tom”

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American Journal of Plant Sciences 2024年第5期15卷 349-358页

作者： arthur B. Rates Daniela Boanares Daniele S. G. Pianetti Felipe Della-Torre Joni E. Lima Marcel G. c. França Department of Botany and Plant Physiology Laboratory Federal University of Minas Gerais Belo Horizonte Brazil

The spatial pattern distribution of plant hormones in response to aluminum (Al) toxicity in roots remains to be shown. This study was performed to assess the root hormonal accumulation and gene expression in response to Al toxicity in five transgenic miniature dwarf tomatoes cv. Micro-Tom (MT). MT and MT transgenics to acid indole acetic, cytokinin, gibberellin, abscisic acid and ethylene were cultivated in nutrient solutions containing different Al concentrations. Root growth elongation was measured and cellular damage was visualized by staining Evans’s blue. The GUS reporter gene staining technique was used to visualize hormonal changes in MT apex root tissues. Data indicated that the MT is sensitive to Al that induced significant growth inhibition and cellular damage. Al concentration of 27 μM was significantly toxic, inducing root apex darkening and inhibition of root development. The qualitative evaluation of GUS reporter gene expression showed intense crosstalk among all hormones studied, underscoring the complexity of signaling induced by Al in apex roots. Results point out to a major understanding of the hormonal signaling in response to Al toxicity, which may induce a change of root growth and architecture with growth inhibition and cell constraints modulated by all different hormones evaluated.

关键词： Gene Reporter Metal Plant Hormones Root Staining

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： Leonardo Goliatt c.M.Saporetti L.c.Oliveira E.Pereira Department of computational and Applied Mechanics Federal University of Juiz de Fora Department of computational Modeling Polytechnic Institute Rio de Janeiro State University Petrobras Department of Stratigraphy and Paleontology Rio de Janeiro State University

Rock samples' TOc content is the best indicator of the organic matter in source rocks. The origin rock samples' analysis is used to calculate it manually by specialists. This method requires time and resources because it relies on samples from many well intervals in source rocks. Therefore, research has been done to aid this effort. Machine learning algorithms can estimate total organic carbon instead of well logs and stratigraphic studies. In light of these efforts, the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and precision. Genetic algorithms, differential evolution, particle swarm optimization, grey wolf optimization, artificial bee colony, and evolution strategies were used to improve machine learning models to predict TOc. The six metaheuristics were integrated into four machine learning methods: extreme learning machine, elastic net linear model, linear support vector regression, and multivariate adaptive regression splines. core samples from the YuDong-Nan shale gas field, located in the Sichuan basin, were used to evaluate the hybrid strategy. The findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict TOc. The results show that, independent of the metaheuristic used to guide the model selection, optimized extreme learning machines attained the best performance scores according to six metrics. Such hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning Evolutionary algorithms Geology

Recent advances on bismuth oxyhalides for photocatalytic cO_(2)reduction

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Journal of Environmental Sciences 2024年第6期140卷 183-203页

作者： Liangpang Xu Jimmy c.Yu Ying Wang Department of chemistry The Chinese University of Hong KongShatinNew TerritoriesHong Kong 999077China

Photocatalytic conversion of cO_(2)into fuels such as cO,cH_(4),and cH_(3)OH,is a promising approach for achieving carbon *** oxyhalides(BiOX,where X=cl,Br,and I)are appropriate photocatalysts for this purpose due to the merits of visible-light-active,efficient charge separation,and easy-to-modify crystal structure and surface *** practical applications,multiple strategies have been proposed to develop high-efficiency BiOX-based *** review summarizes the development of different approaches to prepare BiOX-based photocatalysts for efficient cO_(2)*** the review,the fundamentals of photocatalytic cO_(2)reduction are ***,several widely used modification methods for BiOX photocatalysts are systematacially discussed,including heterojunction construction,introducing oxygen vacancies(OVs),Bi-enrichment,heteroatom-doping,and morphology ***,the challenges and prospects in the design of future BiOX-based photocatalysis for efficient cO_(2)reduction are examined.

关键词： Bismuth oxyhalides Photocatalysis cO_(2)reduction Modification methods

Results of Surgical Management of Malignant Obstruction of the common Bile Duct in Yaoundé

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Surgical Science 2024年第4期15卷 265-277页

作者： Eric Patrick Savom Gaël Tsanga Nomo Richard II Mbele Mahamat Yannick Ekani Boukar cédric Paterson Atangana Fred Dikongue Dikongue Guy Aristide Bang arthur Essomba Yaoundé General Hospital Yaound&#233 Cameroon Faculty of Medicine and Biomedical Sciences of the Universityof Yaoundé I Yaound&#233 Cameroon Faculty of Health Sciences University of Buea Buea Cameroon Faculty of Medicine and Biomedical Sciences of the University of Dschang Dschang Cameroon Yaoundé Teaching Hospital Yaound&#233 Cameroon

Introduction: In cameroon, surgery remains the only approach in malignant obstructions of the common bile duct (MOcBD) even in palliative situations. The aim of this work was to describe the modalities of surgical treatment of MOcBD, evaluate the results and detect the factors associated with postoperative morbidity and mortality. Patients and Methods: We conducted an analytical observational study, with retrospective data collection from the files of patients operated upon for MOcBD. This was done in four referral hospitals in the city of Yaoundé for a 42-month period spanning from January 1, 2020 to June 30, 2023. Demographic data, clinical presentation, surgical data, and 30-day postoperative outcomes were collected. Results: We collected 71 files. The sex ratio was 1.4 and the mean age was 56 ± 11 years. Fifty-three (53) patients (74.6%) were overweight or obese and 10 patients (14.1%) were hypertensive. A clinical cholestasis syndrome was present in 69 patients (97.2%). Fifty-five (55) patients (77.5%) had a cancer of the head of the pancreas, 8 patients (11.3%) had an extra-hepatic cholangiocarcinoma and 8 patients (11.3%) had an ampullary adenocarcinoma. Eight (8) resections (11.3%) with curative intent had been carried out and in 63 cases (88.7%), surgery was palliative. Postoperative morbidity was 55.7%, influenced by advanced WHO stage (p = 0.02). Postoperative mortality was 25.7%, associated with a high ASA score (p = 0.01). conclusion: Pancreatic head cancer is the main etiology of malignant obstructions of the common bile duct in cameroon. Surgical treatment is most often palliative. Postoperative morbidity and mortality are high, influenced by high WHO and ASA scores.

关键词： Malignant Obstruction common Bile Duct Palliative Treatment Morbidity Mortality

Exercise immunology:Novel insights

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Journal of Sport and Health Science 2024年第3期13卷 277-279,I0001页

作者： David c.Nieman Human Performance Laboratory Appalachian State UniversityNorth Carolina Research CampusKannapolisNC 28081USA

The coronavirus disease 2019(cOVID-19)pandemic heightened worldwide attention on the influence of exercise on the immune *** were raised about whether regular moderate-to-vigorous physical activity(MVPA)could help prevent cOVID-19 or mitigate symptoms when *** MVPA bolster immunity among those most prone to cOVID-19 including the elderly,obese,and immunocompromised patients?Does regular MVPA dampen systemic inflammation,thereby lessening the cOVID-19 cytokine storm?

关键词： immunity inflammation thereby

Key Technologies and Prospects for Electric Vehicles Within Emerging Power Systems: Insights from Five Aspects

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cSEE Journal of Power and Energy Systems 2024年第2期10卷 439-447页

作者： Yalun Li Minggao Ouyang c.c.chan Xueliang Sun Yonghua Song Wei cai Yilin Xie Yuqiong Mao Department of Electrical Engineering and School of Vehicle and MobilityTsinghua UniversityBeijing 100084China School of Vehicle and Mobility Tsinghua UniversityBeijing 100084China Department of Electrical and Electronic Engineering The University of Hong KongHong Kong 999077China Department of Mechanical and Materials Engineering University of Western OntarioLondonON N6A 3K7Canada State Key Laboratory of Internet of Things for Smart city University of MacaoTaipaMacao 999078China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China School of Electrical and Electronic Engineering Harbin University of Science and TechnologyHarbin 150080China

The energy revolution requires coordination in energy consumption, supply, storage and institutional *** energy generation technologies, along with their associated costs, are already fully equipped for large-scale ***, energy storage remains a bottleneck, and solutions areneeded through the use of electric vehicles, which traditionallyplay the role of energy consumption in power systems. Toclarify the key technologies and institutions that support EVsas terminals for energy use, storage, and feedback, the cSEEJPES forum assembled renowned experts and scholars in relevantfields to deliver keynote reports and engage in discussions ontopics such as vehicle–grid integration technology, advancedsolid-state battery technology, high-performance electric motortechnology, and institutional innovation in the industry *** experts also provided prospects for energy storage andutilization technologies capable of decarbonizing new powersystems.

关键词： Electric vehicles engineering philosophy highpower density motor new power system solid state batteries vehicle grid integration.

HI in High Gas-phase Metallicity Dwarf Galaxy WISEA J230615.06+143927.9

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Research in Astronomy and Astrophysics 2024年第1期24卷 292-299页

作者： Yan Guo c.Sengupta T.c.Scott P.Lagos Y.Luo Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China Institute of Astrophysics and Space Sciences(IA Porto) Rua das Estrelas4150-762PortoPortugal

We present resolved Giant Metrewave Radio Telescope H I observations of the high gas-phase metallicity dwarf galaxy WISEA J230615.06+143927.9(z = 0.005)(hereafter J2306) and investigate whether it could be a Tidal Dwarf Galaxy(TDG) candidate. TDGs are observed to have higher metallicities than normal dwarfs. J2306 has an unusual combination of a blue g-r color of 0.23 mag, irregular optical morphology and high-metallicity(12 +log(O/H) = 8.68 ± 0.14), making it an interesting galaxy to study in more detail. We find J2306 to be an H I rich galaxy with a large extended, unperturbed rotating H I disk. Using our H I data we estimated its dynamical mass and found the galaxy to be dark matter(DM) dominated within its H I radius. The quantity of DM, inferred from its dynamical mass, appears to rule out J2306 as an evolved TDG. A wide area environment search reveals J2306 to be isolated from any larger galaxies which could have been the source of its high gas metallicity. Additionally, the H I morphology and kinematics of the galaxy show no indication of a recent merger to explain the *** detailed optical spectroscopic observations of J2306 might provide an answer to how a seemingly ordinary irregular dwarf galaxy achieved such a high level of metal enrichment.

关键词： galaxies:abundances galaxies:dwarf galaxies:irregular radio lines:galaxies radio lines:ISM